pyspnego

What's Changed

• Fix up NTLM Single Host unpacking by @jborean93 in #102

Full Changelog: v0.12.0...v0.12.1

What's Changed

• Update build deps and update Python versions by @jborean93 in #98
• Add support for Keytabs on Windows by @jborean93 in #99
• Avoid capturing stack frames in gss.py by @SquidDev in #100

0.12.0 - 2025-09-03

• Drop support for Python 3.7 - new minimum is 3.9+
• Add official support for Python 3.14
• Fix CredSSP server certificate generation to limit CN name to 64 characters
• Added support for using the KerberosKeytab on SSPI/Windows with Kerberos authentication
• Added support for specifying credentials for spnego.server using the credentials kwarg. This currently only works on Windows/SSPI when specifying a keytab credential for the service

New Contributors

• @SquidDev made their first contribution in #100

Full Changelog: v0.11.2...v0.12.0

What's Changed

• Fix CredSSP acceptor with LibreSSL by @jborean93 in #92
• Bump dev deps and add 3.13 support by @jborean93 in #93
• Update integration tests for 3.13 by @jborean93 in #94

0.11.2 - 2024-11-12

• Fix up CredSSP acceptor when running with a LibreSSL based Python install (OpenBSD)
• Added official support for Python 3.13

Full Changelog: v0.11.1...v0.11.2

What's Changed

• Fix deprecation warning for Cryptography 44.0.0 or newer by @hamarituc in #87

0.11.1 - 2024-07-24

• Import ARC4 cipher from the new decrepits module sub-package, this removes the warning issued in newer versions of the cryptography library

New Contributors

• @hamarituc made their first contribution in #87

Full Changelog: v0.11.0...v0.11.1

What's Changed

• Add support for gMSA/machine passwords by @jborean93 in #77
• Move away from dep datetime call by @jborean93 in #79
• Update CI action versions by @jborean93 in #80
• Bump dev dependencies by @jborean93 in #82
• Fix handling of empty passwords by @psfrolov in #73
• Update CI matrix and dev deps by @jborean93 in #83
• Tidy up NTLM error messages and update changelog by @jborean93 in #84
• Prepare for v0.11.0 release by @jborean93 in #85

0.11.0 - 2024-06-12

• Support input password string encoded with the surrogatepass error option
  • This allows the caller to provide a password for a gMSA or machine account that could contain invalid surrogate pairs for both NTLM and Kerberos auth.
• Stop using deprecated datetime.dateime.utcnow() for CredSSP acceptor context
• Treat an empty string as a valid password, None is kept as use the cached credential
• Improve the exception shown when no password was provided and no cached credential was available

New Contributors

• @psfrolov made their first contribution in #73

Full Changelog: v0.10.2...v0.11.0

What's Changed

• Rename sspic to sspilib by @jborean93 in #72

Full Changelog: v0.10.1...v0.10.2

What's Changed

• Rename sspi dep to sspic by @jborean93 in #70

Full Changelog: v0.10.0...v0.10.1

What's Changed

• Migrate SSPI to external library by @jborean93 in #69

0.10.0 - 2023-09-27

• Drop support for Python 3.7 - new minimum is 3.8+
• Moved SSPI bindings out into a separate package called sspi
  • This simplifies this project as it doesn't have to worry about SSPI correctness
  • The sspi package improves performance and memory allocation with a more robust API
  • Fixes an issue with Cython 3 allowing it to align with more modern versions going forward

Full Changelog: v0.9.2...v0.10.0

What's Changed

• Added Python 3.12 win wheels and test in CI by @jborean93 in #67

0.9.2 - 2023-08-29

• Added Python 3.12 wheel for Windows

Full Changelog: v0.9.1...v0.9.2

What's Changed

• Set NTLM Negotiate Version field by @jborean93 in #65

0.9.1 - 2023-06-14

• Always set the NTLMSSP_REQUEST_VERSION flag on the NTLM Negotiate message
  • This aligns the behaviour with how SSPI generates this message

Full Changelog: v0.9.0...v0.9.1

• Added the spnego.ContextReq.dce_style flag to enable DCE authentication mode
  • This is used in protocols like RPC/DCE
• The value for spnego.iov.BufferType.sign_only on SSPI has changed from representing SECBUFFER_MECHLIST to SECBUFFER_READONLY_WITH_CHECKSUM
  • This is to better match what sign_only means when using it with GSSAPI
  • It is needed to support RPC encryption and signature headers on SSPI
  • The use of SECBUFFER_MECHLIST is not seen in any examples in the wild and is most likely an internal flag
• Added the IOV buffer type spnego.iov.BufferType.data_readonly
  • For SSPI this corresponds to SECBUFFER_DATA | SECBUFFER_READONLY
  • For GSSAPI this corresponds to GSS_IOV_BUFFER_TYPE_EMPTY
  • As GSSAPI has no actual equivalent to this the empty buffer type is used which in testing results in compatible buffers
  • This is used for DCE/RPC wrapping when the PDU header and sec trailer are not signed but are included in the wrap_iov buffers.
• Added limited support for wrap_iov and unwrap_iov in the Python NTLM context provider.
  • This currently only supports spnego.iov.BufferType.header, spnego.iov.BufferType.data, spnego.iov.BufferType.sign_only, spnego.iov.BufferType.data_readonly, and spnego.iov.BufferType.stream
  • header
    • wrap_iov: Used to place the resulting signature in the buffer
    • unwrap_iov: Used as the signature source for validation
  • data
    • wrap_iov: Data to be encrypted/sealed
    • unwrap_iov: Data to be decrypted/unsealed
  • sign_only
    • wrap_iov: Data to be included in the signature/header generation
    • unwrap_iov: Data to be included in the signature/header verification
  • data_readonly is treated the same as sign_only
  • stream
    • wrap_iov: Not supported
    • unwrap_iov: Contains the full value to decrypt with the headers in the beginning, must be coupled with a subsequent data buffer of the type data to place the decrypted value into
  • The behaviour used here is modelled as closely as possible to how SSPI works but not all the permutations have been tested.
  • The header/signature will be generated from the data, sign_only, data_readonly values concat together in the order they are provided.
• Added the query_message_sizes() function on a context to retrieve the important message sizes
  • Currently this only contains the size of the message header, also known as the signature or security trailer

• Added the spnego.ContextReq.no_integrity flag to disable integrity/confidentiality on Kerberos/Negotiate contexts
  • This is used by authentication contexts that need to disable integrity/confidentiality explicitly
  • An example would be the LDAP SASL GSS-SPNEGO where the context flags control the SSF flags
• Added optional kwargs to step() on a security context channel_bindings
  • This can be used to supply the channel bindings when performing a context step rather than when creating the context

• Added support for decoding the following TLS payloads with python -m spnego --token ...
  • Client Hello
  • Server Hello
  • Certificate
  • Server Key Exchange
  • Client Key Exchange
  • Certificate Request
• Added the new_context() method on the context proxies to provide an easy and efficient way to re-use the context credentials and options for a new context
• Removed use of gssntlmssp to simplify codebase and ensure a consistent experience across OS versions
  • Using NTLM on a non-Windows system will use the Python NTLM implementation instead

• Ignore GSS_S_NO_CONTEXT errors on GSSAPI after stepping through the token exchange before the context is complete
  • This is raised by MIT krb5 before 1.14.x and can be ignored

• Fix up sdist and wheels to include py.typed type annotation marker

• Added Python 3.11 wheel

• Drop support for Python 3.6 - new minimum is 3.7+
• Moved setuptools config into pyproject.toml and made Cython a build requirement for Windows
  • For most users this is a hidden change
  • If a tool follows the PEP 517 standard, like pip, this build dependency will work automatically
  • The pre cythonised files are no longer included in the sdist going forward

• Fix str of enum values when running in Python 3.11 to be consistent with older versions
• Support gssapi on 1.5.x which comes with RHEL 8.

• Fix heap allocation errors when running with heap allocation monitoring on Windows

• Added custom MD4 hashing code for NTLM to use.
  • Newer Linux distributions ship with OpenSSL 3.x which typically disables MD4 breaking the use of hashlib.new('md4', b"")
  • Using this custom code allows NTLM to continue to work
  • While it's bad to continue to use older hashing mechanisms in this case there is no valid alternative available

• Call gss_inquire_sec_context_by_oid(ctx, spnego_req_mechlistMIC_oid) when using pure NTLM over GSSAPI to ensure the token contains a MIC

• Added the auth_stage extra_info for a CredSSP context to give a human friendly indication of what sub auth stage it is up to.
• Added the protocol_version extra_info for a CredSSP context to return the negotiated CredSSP protocol version.
• Added the credssp_min_protocol keyword argument for a CredSSP context to set a minimum version the caller will accept of the peer.
  • This can be set to 5+ to ensure the peer supports and applies the mitigations for CVE-2018-0886.
• Added safeguards when trying to retrieve the completed context attributes of NegotiateProxy before any contexts have been set up (https://github.com/jborean93/pyspnego/issues/33)

Features

• Add usage argument for tls.default_tls_context to control whether the context is for a initiator or acceptor
• Add type annotations and include py.typed in the package for downstream library use
• Expose the ContextProxy class for type annotation use
• Added get_extra_info to ContextProxy to expose a common way to retrieve context specific information, this is currently used by CredSSP to retrieve
  • client_credential: The delegated client credential for acceptors once the context is complete
  • sslcontext: The SSL context used to create the TLS object
  • ssl_object: The TLS object used during the CredSSP exchange
• The client_credential property on CredSSP has been removed in favour of `context.get_extra_info('client_credential')
• Added support for custom credential types
  • Can be used to for things like NTLM authentication with NT/LM hashes, Kerberos with a keytab or from an explicit CCache, etc
• Support calling SSPI through pyspnego's Negotiate proxy context
  • This allows users on Windows to still use Negotiate auth but with a complex set of credentials
  • Also opens up the ability to use Negotiate but only with Kerberos auth

Deprecations

• The username and password property on the auth context object are deprecated and will return None until it is removed in a future release

• Do not convert GSSAPI service to lowercase for GSSAPI and uppercase for SSPI
  • SPNs are case insensitive on Windows but case sensitive on Linux
  • Convering the service portion to upper or lower case could cause problems finding the target server on non-Windows GSSAPI implementations

Packaging Changes

• Changed project structure to a src layout
• Include both Cython pyx/pyd and C files for SSPI in the sdist generated
• Added Python 3.10 wheel

Bugfixes

• Ensure bad SPNEGO token inputs are raised as InvalidTokenError rather than struct.error

Breaking Changes

• Drop support for Python 2.7 and 3.5 - new minimum is 3.6+
• Made the gss, negotiate, ntlm, sspi exports private, use the spnego.client and spnego.server functions instead
  • A deprecation warning is raised when importing from these package directly and this will be removed in the next major release

Features

• Added support for CredSSP authentication using protocol='credssp'
• Allow optional keyword arguments to be used with spnego.client and spnego.server to control authentication specific options

Bugfixes

• Use Kerberos API to acquire Kerberos credential to get a forwardable token in a thread safe manner
• Fix default credential logic when no username is provided based on GSSAPI rules rather than just the default principal - https://github.com/jborean93/pyspnego/issues/15
• Ignore SPNEGO mechListMIC if it contains the same value as the responseToken due to an old Windows SPNEGO logic bug - https://github.com/krb5/krb5/blob/3f5a348287646d65700854650fe668b9c4249013/src/lib/gssapi/spnego/spnego_mech.c#L3734-L3744
• Do not use SSPI when auth='ntlm' and the password is in the form {lm_hash}:{nt_hash}

• This will be the last release that supports Python 2.7 and 3.5
• Change enum type of iov.BufferType to IntEnum to fix load on Python 3.10 - https://github.com/jborean93/pyspnego/issues/10
• Make pyspnego-parse and entry point which uses __main__.py in the spnego package
  • This allows Windows (and Linux) users to use the parser script by running python -m spnego --token ...

• Respect NETBIOS_COMPUTER_NAME when getting the workstation name for NTLM tokens. This matches the behaviour of gss-ntlmssp to ensure a consistent approach.

• Only send negState: request-mic for the first reply from an acceptor for Negotiate auth.
  • Strict interpretations of SPNEGO will fail if the initiator sends this state as it is against the RFC.

• Added Python 3.9 to CI and build Windows wheel for this version

• Fix up WinRM wrapping on SSPI

• Include the cython files in the built sdist

Initial release of pyspnego

0.1.0rc4 - 2020-07-11

• Added the wrap_winrm and unwrap_winrm methods to a context to cover the complexity of WinRM wrapping
• Re-added ContextReq.delegate_policy and just make it optional based on the python-gssapi version installed

0.1.0rc3 - 2020-07-09

• Remove ContextReq.delegate_policy because python-gssapi does not support flags that they do not define

0.1.0rc2 - 2020-07-07

• Ensure any explicit Kerberos credentials have the forwardable flags set when ContextReq.delegate is requested
• Fix protocol check to use the options passed in by the caller

0.1.0rc1 - 2020-07-07

• Expanded pyspnego-parse help messages a bit more
• Added the yaml extras group to install ruamel.yaml which is an optional feature for pyspengo-parse

0.1.0b2 - 2020-07-05

• Fix context has been set up check on Windows initiator when running against localhost
• Ensure built wheels are not built with linetrace=True which breaks debugging in PyCharm

0.1.0b1 - 2020-07-04

First beta release of pyspnego.